import { NextRequest, NextResponse } from "next/server";
import { getServerSession } from "next-auth/next";
import { authOptions } from "@/app/api/auth/options";
import { prisma } from "@/lib/prisma";

/**
 * Check if a user exists in the database
 */
async function userExists(userId: string): Promise<boolean> {
  try {
    const user = await prisma.user.findUnique({
      where: { id: userId },
      select: { id: true }
    });
    return !!user;
  } catch (error) {
    console.error(`Error checking if user exists:`, error);
    return false;
  }
}

// GET - Retrieve all announcements (with role filtering)
export async function GET(req: NextRequest) {
  try {
    const session = await getServerSession(authOptions);
    
    if (!session) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }

    // Get user role from session
    const userRole = session.user.role || [];
    const roles = Array.isArray(userRole) ? userRole : [userRole];
    
    // Query announcements based on role
    const announcements = await prisma.announcement.findMany({
      where: {
        OR: [
          { targetRoles: { has: "all" } },
          { targetRoles: { hasSome: roles } }
        ]
      },
      orderBy: {
        createdAt: "desc"
      },
      include: {
        author: {
          select: {
            id: true,
            email: true
          }
        }
      }
    });
    
    return NextResponse.json(announcements);
  } catch (error) {
    console.error("Error fetching announcements:", error);
    return NextResponse.json({ error: "Failed to fetch announcements" }, { status: 500 });
  }
}

// POST - Create a new announcement
export async function POST(req: NextRequest) {
  try {
    const session = await getServerSession(authOptions);
    
    if (!session) {
      return NextResponse.json({ error: "Unauthorized" }, { status: 401 });
    }
    
    // Check if user has admin, entrepreneurship, or communication role
    const userRole = session.user.role || [];
    const roles = Array.isArray(userRole) ? userRole : [userRole];
    const hasAdminAccess = roles.some(role => 
      ["admin", "entrepreneurship", "communication"].includes(role)
    );
    
    if (!hasAdminAccess) {
      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
    }
    
    // Parse request body
    const { title, content, targetRoles } = await req.json();
    
    // Validate request body
    if (!title || !content || !targetRoles || !targetRoles.length) {
      return NextResponse.json({ error: "Missing required fields" }, { status: 400 });
    }
    
    // Verify user exists in database (using session user id)
    console.log("Verifying user ID:", session.user.id);
    
    const userExistsInDB = await userExists(session.user.id);
    
    if (!userExistsInDB) {
      console.error("User not found in database:", session.user.id);
      return NextResponse.json({ 
        error: "User not found",
        details: `The user ID from your session (${session.user.id}) doesn't exist in the database. This may be due to a session/database mismatch or the user hasn't been synced to the application database.` 
      }, { status: 400 });
    }
    
    // Create new announcement
    const announcement = await prisma.announcement.create({
      data: {
        title,
        content,
        targetRoles,
        authorId: session.user.id
      }
    });
    
    return NextResponse.json(announcement, { status: 201 });
  } catch (error) {
    console.error("Error creating announcement:", error);
    // Return more detailed error information
    const errorMessage = error instanceof Error ? error.message : "Unknown error";
    // Use a type guard to safely access the 'code' property
    const errorCode = typeof error === 'object' && error !== null && 'code' in error 
      ? (error as { code: unknown }).code?.toString() || "UNKNOWN"
      : "UNKNOWN";
    
    return NextResponse.json({ 
      error: "Failed to create announcement",
      details: errorMessage,
      code: errorCode
    }, { status: 500 });
  }
}